Electrical connector having improved contact-terminal means



Sept. 15, 1964 J. F. HEALY ELECTRICAL. CONNECTOR HAVING IMPROVEDCONTACT-TERMINAL MEANS Filed Dec. 11, 1961 2 Sheets-Sheet 1 Sept. 15,1964 J. F. HEALI.Y

ELECTRICAL CONNECTOR HAVING IMPROVED CONTACT-TERMINAL MEANS 2Sheets-Sheet 2 Filed Dec. 11, 1961 a; 76' ea as ss INVENTOR im? We ATTRNEYS United States Patent This invention relates generally toelectrical cable or cord connectors-and particularly to improvementstherein in the construction and mounting of the contact-terminal meansthereof.

In electrical connectors of the connector body and cap type which aredesigned to effect and permit selective connection and disconnection ofelectrical cable or cord, it is necessary and conventional to include ineach connector component electrical contact means and electricalterminal means for effecting electrical connection of the usual wires ofthe cable or cord to the-contact means. Usually the connector componentcomprises abody of electrical insulation material, frequently a suitableplastic material, to which is physically attached the contact' means andthe terminal means, which we usually electrical conducting metallicmembers. In the usual arrangement, the contact means is disposed to beaccessible from the exterior of the connector component to be availablefor operative association with the cooperating contact means of anassociated connector component, and the electrical wires of the cable orcord are connected to the terminal means therefor on the interior of theconnector component, which usually includes a protective housing and/ orshell of some type. Frequently the contact means and the terminal meansare mounted on spaced walls on opposite sides of the electricalinsulation body, one on the exterior and the other on the interiorthereof. As it is necessary that the contact means andterminal means beelectrically connected, this connection is frequently efiected by theprovision of a metallic bushing which is disposed in and extends throughthe electrical insulation body completely through the walls thereof, andhas an end thereof projecting through one wall of the body and connectedto the contact means and the opposite end thereof projecting through theother wall of the body and connected to the terminal means. Theconnections or joints between the bushing endsand the contact means andterminal means are usually effected by spinning over the bushing ends.This arrangement is widely employed in practice in the electrical wiringdevice industry. It has been ascertained in practice, however, that thisarrangement is less than completely satisfactory. For example, it hasbeen ascertained in practice that the quality of the joints between therespective bushing ends and he terminal means and the contact means isvariable as it is dependent upon the nature of the spunover connectionsbetween the bushing ends and the contact means and terminal means. .Ithas been found in practice that the quality of these joints is dependentupon the amount of pressure applied by the operatorof. the mac'nne whichspins over the ends of the bushings to form the joints. It has also beenfound in practice that the prior art arrangement provides two locations,namely, the joints between the bushing ends and the contact means andterminal means, where overheating and structural failure frequentlyoccur.

It i a further object of the invention to provide an electricalconnectors having improved contact-terminal means, and particularlywherein such improved contactterminal means includes the provision fordirect electrical connection between the usual terminal binding screwsforming a part of the terminal means and the contacts of ice 2 thecontact means without the presence of any intervening joints.

It is another object of the invention to provide an improved electricalconnector as set forth in the preceding paragraph which, thoughfiuictionally superior to prior art constructions, is less costly tomanufacture.

It is still another object of the invention to provide an improvedelectrical connector wherein the contactterminal means is structurallystronger and more durable than prior art arrangements.

It is a further object of the invention to provide an improvedelectrical connector wherein the usual bushing which connects the usualterminal plate and the usual contact mounting plate is eliminated, alongwith the usual joints at the bushing ends.

It is a still further object of the invention to provide an improvedcontact-terminal construction and mounting for an electrical wiringdevice wherein the contactterminal means comprises essentially a unitarycontactterminal member which is mounted on a body of plastic insulationmaterial and which when mounted thereon is retained thereon by its ownform.

Other objects and further details of that which I believe to be noveland my invention will be clear from the following description and claimstaken with the accompanying drawings, wherein:

PEG. 1 is a perspective view of an electrical connector cap whichincorporates the invention;

FIG. 2 is a longitudinal sectional view thereof taken substantially online 2-2 of FIG. 1;

FIG. 3 is a sectional view thereof taken substantially on line 33 ofFIG. 2;

FIG. 4 is an enlarged sectional view taken substantially on line 44 ofFIG. 3 with portions omitted for the sake of clarity;

FIG. 5 is an enlarged sectional view taken substantially on line 55 ofFIG. 3 with portions omitted for the sake of clarity;

FIG. 6 is a bottom plan view of the insulation base per se which forms apart of the body of the cap;

FIG. 7 is a top plan view thereof;

FIG. 8 is an enlarged sectional view taken online 8-8 of FIG. 6:

FIG. 9 is an enlarged sectional view taken on line 9-9 of FIG. 6;

FIG. 10 is an enlarged side elevational view of a contact-terminalmember illustrated in solid lines in the original position it occupiesprior to being fully mounted on the cap base and with the upper legthereof shown in dotted lines in the position which it occupies whenfully mounted;

FIG. 11 is a perspective view thereof;

FIG. 12 is a sectional view showing in solid lines a contact-terminalmember mounted on .the cap base, and showing the upper leg of the memberindotted lines in the original position which it occupies prior to finalassembly; and

FIG. 13 is a top perspective view of a cap base showing threecontact-terminal members mounted thereon.

In the drawings there is illustrated an electrical connector cap whichincorporates the invention wherein the novel contact-terminal meansthereof include male contact blades; however, it should be fullyunderstood that the improved contact-terminal means and their mountingmay be incorporated into other types of electrical wiring devices, suchas connector bodies or receptacles where female contacts are employed,and that the disclosure in detail of the invention herein in anelectrical connector cap is merely exemplary of one particularly usefulapplication of the invention. It should be particularly realized thatthe improved contact-terminal means may 3 be incorporated into bases fortubes, such as electronic and photoelectric tubes.

The disclosed electrical connector cap is designated generally byreference numeral and it generally comprises a two-part body preferablymade of a suitable plastic electrical insulation material which partsherein will be referred to for convenience as the base 12 and the top14, and a cylindrical outer metallic shell 16 which is assembled to thebase 12 and the top 14 by a plurality of tie bolts 18 which pass throughaligned openings 13 and 15, respectively, in the parts and have theirthreaded ends 20 anchored in threaded bosses 22 formed in the top wallof shell 16. The cap 10 also includes a plurality of uniquelyconstructed and mounted contact-terminal members which will hereinafterbe described in greater detail, and a suitable known cord grip 24 forgripping and strain-relieving an electrical cable or cord 26 having aplurality of bared electrical wires 28 which are individuallyelectrically connected to the terminal portions of the contact-terminalmembers by binding screws 30. As illustrated in FIG. 1, the contactportion of one of the terminal-contact members is formed of a differentconfiguration from the other two so as to function as a key forcontrolling insertion of the cap into a cooperating connector body orreceptacle in a predetermined manner, and each of the contact portionsincludes a laterally extending portion which functions as aninterlocking lug. The number of contact port-ions and their particularconfigurations form no specific part of the invention; however, asillustrated, there are three interlocking contact blades, one of whichis distinctively configured and may conveniently function as a groundingcontact.

The invention has particular regard with relation to the base 12, theterminal-contact members and the mounting of the latter on the former.There are three contactterminal members illustrated in the drawings;however, two of them are constructed and mounted in a similar manner,and the third is constructed and mounted in a different manner.Therefore, the two similar members are generally designated by the samereference numeral 32, and the third by reference numeral 34 and eachwill be separately described in detail. With reference to FIGS. 10 and11, a terminal-contact member 32 may be observed. It comprisesessentially a. bent strip of metal including a slightlycross-sectionally curved elongated blade portion 36 having a lateral lug38 formed thereon at its free end and a C-shaped mounting portion 40comprising generally parallel spaced lower and upper legs 42, 44,respectively, connected at adjacent ends by connecting leg 46. The endof lower leg 42 opposite the one connected to connecting leg 46 isconnected to the upper end of blade portion 36. Adjacent to theconnection of lower leg 42 and blade portion 36 on opposite sides of leg42 extends a pair of locating tabs 48. Centrally of and in the lower leg42 is formed a threaded opening 50. In the upper leg 44 there is formeda plain opening 52 of larger diameter than opening 50, which openingsare coaxially aligned when the terminal-contact member is fully mountedon base 12, as shown in FIG. 12. A slot 54 of narrower width than thediameter of the opening 52 but communicating therewith at one sidethereof is formed through adjacent portions of the upper leg 44 and theconnector leg 46 primarily to reduce weight and facilitate bending ofthe metallic strip which forms the terminal-contact member. The end ofupper leg 44 opposite to the one connected to connecting leg 46 has ananchoring tab 56 of reduced width extending at a slight angle therefrom.It will be understood by those skilled in the art that terminal-contactmembers 32 may be made of an appropriate metal having the desirableelectrical conducting characteristics and may be formed thereof in anyconvenient manner as by stamping and bending, and in the case of theopening 50, by tapping a thread. Prior to mounting, the terminal-contactmembers 32 are disposed as illustrated in full lines in FIGS. 10 and 11,and it will there be observed that the upper leg 44 is not parallel tothe lower leg 42, but inclined relative thereto to diverge therefrom,and therefore, the openings 50, 52 are not coaxial at this time;however, after being fully mounted on the base 12, the legs 42, 44 areparallel and their openings 50, 52 are coaxial, as can be seen in FIG.12.

As can best be seen in FIGS. 6, 7, 8 and 13, the base 12 is roughlyconfigured as a thin solid section of a cylinder, having a pair ofspaced flat walls and a cylindrical side wall. The base 12 is recessedin three angularly spaced peripheral locations to accommodate themounting portions of terminal-contact members 32, 34; however, only thetwo recessed locations which accommodate the members 32 will bedescribed at this point. With reference to FIGS. 6 and 7, the lower side58 of the base is illustrated in FIG. 6 and the upper side 60 thereof isillustrated in FIG. 7. The two recessed portions for accommodatingmembers 32 are generally designated 62, and the recessed portion foraccommodating the terminalcon-tact member 34 is designated generally byreference numeral 64.

Each recessed portion 62 comprises a shallow, generally rectangularrecess 66 having a pair of oppositely extending small shallow recesses68 formed in the bottom side 58; a radially inwardly and axiallyextending cutout portion 70 formed in the periphery of base 12, and ashallow, generally rectangular recess 72 formed in the top surface 60having radially and axially inwardly extending smaller recess 74 at theradial inner end thereof. As can best be seen in FIG. 8, at one sidewall of each small recess 68 the adjacent rim portion of the bottom wall58 is inclined at 76; a threaded bore 78 is formed in and extendscompletely through the base 12, and recess 74 inclines axially inwardly.To mount a terminalcontact member 32 to the base 12, its mountingportion 40 is juxtaposed to a recessed portion 62, it should be notedthat at this time the upper leg 44 thereof is disposed in the dottedline position, and the mounting portion 40 is moved radially inwardlyrelative to the base 12 into a recessed portion 62. The legs 42 and 44of the mounting portion 40 are then forced relatively toward each otherinto final assembled position wherein they are securely mounted on thebase 12, as by being set in a power press. A convenient and effectiveway of accomplishing assembly is to locate the tabs 48 in the recesses68 to properly position leg 42 in recess 66, and then force upper leg 44toward leg 42 to embed its anchoring lug 56 into recess 74. When in thefinal mounted position, the mounting means 40 occupies and ispermanently set in the solid line position shown in FIGS. 4 and 12. Infully mounted condition, the following structural relationship obtains:The legs 42, 46 and 44 of the mounting portion 40 of the member 32 aredisposed respectively in the recesses 66, 70 and 72. The tabs 48 arefirmly seated in the small recesses 68 in the under side 58 of the base,their disposition therein having been facilitated by the inclined sidewalls 76 of the recesses, and the tab 56 is disposed and firmly embeddedin recess 74. Also, threaded bore 78 in the base is aligned with thethreaded opening 50 in the lower leg 42 and the plain opening 52 in theupper leg 44. When in this condition, the contact-terminal members 32are permanently securely mounted on the base 12.

As can best be seen in FIG. 4, a terminal binding screw 30 may then bethreadedly inserted into the assembled terminal-contact member and basesubassembly and have its threaded shank 80 threadedly engage both thethreaded bore 78 and the threaded opening 50 in the lower leg 42. Itshould be particularly noted that the opening 52 in the upper leg 44being of larger diameter than the bore '78 and threaded opening 50,allows the threaded shank 80 to pass through it with ample clearance.Therefore, the binding screw 30 is anchored threadedly in the threadedbore 78 of the base and the threaded opening 50 of the lower leg 42. Ascan best be seen in FIG. 2, a barcd wire 28 may be electricallyconnected to a contact-terminal member 32 by being wrapped around theshank 80 of a terminal binding screw 30 immediately beneath its head andhaving the screw 30 tightened to clamp it in such position between theleg 44 and the underside of the screw head. It should be observed inFIG. 2 that when a wire 28 is electrically connected to leg 44, it isdirectly connected to contact blade 36 through unitary member 32 withoutany intervening joints, and that the binding screw 86 adds additionalstructural strength to the mounting of member 32 on the base 12.

Terminal-contact member 34 is generally similar to members 32 with theexception, as can best be seen in FIG. 5, that the opening $2, in itslower leg 84 of its mounting portion 36 is plain and larger than thescrew shank 89; the opening 88 in the upper leg 90 of its mountingportion is threaded, and the threaded opening 88 is of smaller diameterthan the opening 82, such .as to threadedly engage the threaded shank 8dof a terminal binding screw 30. Otherwise similar and correspondingportions of members 34 to members 32 are designated by the samereference numeral with a prime added. Although slot 91 may be formed inits mounting portion and intersect opening 88, the latter opening isthreaded over a sufficient portion of its periphery to threadedly anchora screw. The terminal-contact member 34 is mounted in recessed portion64, which is generally similar to recessed portions 62 for accommodatingmembers 32, with the exception that the bore 92 which forms a partthereof is not threaded, is of a larger diameter than the bores 78, andopens to the periphery of the base through a communicating slottedpassage 94 (see FIG. 7). Otherwise,

recessed portion 64 is constructed in generally the same manner asrecessed portions 62, and therefore, corresponding elements thereof aredesignated by similar reference numerals with a prime added (seeparticularly FIG. 9). As can best be seen in FIG. 5, the terminalbinding screw 30 associated with terminal-contact member 34 has itsthreaded shank 8i) threadedly anchored in threaded opening 88 in upperleg 90, and the remainder thereof clears the bore 92 in base 12 and theplain opening 82 in the lower leg 84. Therefore, with the member 34, abinding screw 30 is anchored only in the upper leg of the mountingportion. The main practical effect of the different mountings of themembers 32 and 34 resides in the ability of the member 34 to be mountedon the base 12 with a terminal screw already threadedly secured in thethreaded opening 88 in the upper leg 90 thereof, as the slot 94 in thebase will permit this mode of mounting. In practice, where feasible,this mode of mounting is preferred as it can be performed at thefactory. This is desirable in practice, as it enables mass assembly andshipment of connector components with members 34 and their terminalbinding screws already mounted on them. With the mounting for members32, the binding screws must be separately attached to their members 32after the members 32 are mounted on the base. With this mounting,binding screws may be shipped in bulk and attached to members 32 at thepoint of installation or use. It should be clearly understood thateither of the two types of mounting for the contact-terminal members maybe used for any type of contact, the selection being dependent onwhether the binding screws are to be attached at the factory or at thepoint of installation, and not on the type of contact.

In view of the foregoing it will be apparent that an improvedcontact-terminal member has been provided which satisfies each and everyobject of this invention in that an arrangement has been provided inwhich an effective permanent mounting for metallic contact-terminalmembers on a plastic body base has been provided; there are no joints orconnections between the contacts and the terminals, as whereconventional connector bushings are employed; wherein conventionalbushings have been eliminated; the terminal binding screws have directconbinding screws enhance the mounting of the members.

In practice it has been found that in addition to providing afunctionally superior contact-terminal means to prior art arrangementscurrently in vogue, the improved contact-terminal members are actuallyless costly to manufacture and assemble on a base, and savings in theorder of fifty percent have been effected through utilization of theimproved contact-terminal members.

As will be evident from the foregoing description, certain aspects of myinvention are not limited to the particular details of construction ofthe examples illustrated, and I contemplate that various and othermodifications and applications will occur to those skilled in the art.For example, as mentioned above, the illustrated embodiment of theinvention comprises an electrical cable or cord connector cap, but theinvention can be incorporated into other types of electrical wiringdevices, such as connector bodies or caps, or into tubes, such aselectronic or photoelectric tubes. In the latter regard, the subassemblyof base and electrical contact-terminal members, as shown in FIG. 13,can function as a plug base for a tube by having appropriate elementsmounted at the upper legs of the members and an appropriate glassenvelope secured to the base. In this embodiment of the invention thecontacts function as mounting means for the tube and for supplyingelectrical current to the internal tube elements in the glass envelope.It is, therefore, my intention that the appended claims shall cover suchmodifications and applications as do not depart from the true spirit andscope of my invention.

Having thus set forth the nature of my invention, I claim:

1. In an electrical connector: a contact and terminal carrying base madeof an electrical insulating material; a plurality of recessed portionsspaced about the periphery of said base; locating recesses formed insaid base; a plurality of unitary metallic contact and terminal membersindividually supported on and by said base; each of said membersincluding a contact portion and an integral mounting portion; saidmounting portion being C-shaped and having two spaced generally parallellegs and a connecting leg, all being aranged to be wholly disposed insaid recessed portions; said mounting portion including locating tabsdisposable in said locating recesses to properly position said memberson said tabs; said mounting portion including means for contacting andfrictionally gripping said base to anchor and retain the member on saidbase; said mounting portion and base having coaxial openings formedtherein; and a terminal binding screw extending through said openingsand being threadedly anchored in said mounting portion.

2. The device defined in claim 1 wherein one of said spaced legs isdisposed on one side of said base and the other of said spaced legs andsaid contact portion are disposed on the opposite side thereof; theopening in said base is a plain slot which opens to the periphery ofsaid base; and the opening in said one leg is threaded and the openingin said other leg is plain.

3. The device defined in claim 1 wherein one of said spaced legs isdisposed on one side of said base, the other of said spaced legs andsaid contact portion are disposed on the opposite side thereof; theopening in said base is threaded; and the opening in said one leg isplain and the opening in said other leg is threaded.

4. For use in an electrical wiring device, a unitary metalliccontact-terminal member comprising: a contact portion; a C-shapedmounting portion comprising a pair of spaced elongated legs connected atadjacent ends by a connector leg; one of said spaced legs at one of itsends being connected to said contact portion and having laterallyextending locating tab means formed thereon intermediate its ends; theother of said spaced legs having an anchoring tab formed thereon andprojecting at its free of alignable openings formed in said spaced legsfor re 1 ceiving a terminal binding screw; and one of said openingsbeing smaller than the other and threaded.

References Cited in the file of this patent UNITED STATES PATENTS1,536,024 Kvaal Apr. 28, 1925 8 Pattison May 12, Ogg July 21, Ecksteinet a1. Sept. 24, Grohsgal May 21, Ayers Jan. 6, Frekko Oct. 13,

FOREIGN PATENTS Australia. Nov. 25,

4. FOR USE IN AN ELECTRICAL WIRING DEVICE, A UNITARY METALLICCONTACT-TERMINAL MEMBER COMPRISING: A CONTACT PORTION; A C-SHAPEDMOUNTING PORTION COMPRISING A PAIR OF SPACED ELONGATED LEGS CONNECTED ATADJACENT ENDS BY A CONNECTOR LEG; ONE OF SAID SPACED LEGS AT ONE OF ITSENDS BEING CONNECTED TO SAID CONTACT PORTION AND HAVING LATERALLYEXTENDING LOCATING TAB MEANS FORMED THEREON INTERMEDIATE ITS ENDS; THEOTHER OF SAID SPACED LEGS HAVING AN ANCHORING TAB FORMED THEREON ANDPROJECTING AT ITS FREE END; SAID SPACED LEGS INITIALLY DIVERGING FROMSAID CONNECTOR LEG, BUT BEING DEFORMABLE TO A SUBSTANTIALLY PARALLELCONDITION TO MOUNT THE MEMBER ON A SUPPORT; A PAIR OF ALIGNABLE OPENINGSFORMED IN SAID SPACED LEGS FOR RECEIVING A TERMINAL BINDING SCREW; ANDONE OF SAID OPENINGS BEING SMALLER THAN THE OTHER AND THREADED.